The relationship

Harry Potter - J. K. Rowling
M/M
G
The relationship
Summary
"James what ? What did you just say ?""I'm dating Regulus.""James... You're going to have to tell Sirius at some point... He's going to kill you !""Yeah... I know... I keep thinking of how I'm supposed to tell him that I'm dating his younger brother. I asked Regulus if he wanted to do it but he clearly didn't..."
Note
This is my take on how Sirius reacted when he learned that Regulus and James were dating.English is not my first language, I’m sorry for any eventual mistakes. Don’t hesitate to tell me if you see some !I hope you enjoy the story !

“James what ? What did you just say ?”
Marlene, Peter, and James were sitting together on the grass right outside the castle. The three were childhood friends and it had been such a long time that they had a moment like that for themselves. They were always with the rest of the Gryffindors' friends and wanted a little bit of time with just the three of them just like in old times.
It was during this little time together that James decided to confess something to his friends. He had been wanting to tell them the truth for a few weeks but he was terrified of their reaction. Hanging out with his childhood friends made him finally do it.
“Can you repeat that ? I feel like I heard wrong.” Peter was looking at James with wide eyes.
“No, I’m pretty sure you heard right”
“Okay but can you still repeat it because I’m having a hard time comprehending right now.” Marlene added, half sure she was hallucinating.
“Guys… You heard right ! I’m dating Regulus.”
“Like… The Regulus ?”
“Do you know other Regulus ?” James looked at Peter confused.
“So we are talking about Regulus Black, the little brother of your best friend, you’re brother from another mother, platonic soulmate ?”
“Why are you saying it like that ? But yes this Regulus.”
“I feel like it’s incest.” Whispered loudly Peter to Marlene.
“Ew, I don’t want to think about that, that’s disgusting.”
“Can you guys stop saying weird stuff ? It’s not incest okay.”
After that, the three friends continue to talk about James and Regulus’ relationship, with Marlene and Peter asking every question they could possibly think about. At one point during their conversation, which felt more like an interview for James, Marlene suddenly grabbed James' arm and her face looked like she just saw You-Know-Who himself. James and Peter looked at her worriedly waiting for her to tell them what she just thought of.
“James… You’re going to have to tell Sirius at some point… He’s going to kill you !”
“Yeah… I know… I keep thinking of how I’m supposed to tell him that I’m dating his younger brother. I asked Regulus if he wanted to do it but he clearly didn’t…”
Peter burst out laughing before adding “He knows his brother and definitely does not want to be here when Sirius is going to learn it ! Although… I wonder who is he going to be more mad at, you or Regulus ?”
“Peter ! You’re making it worse, now I’m even more panicking about telling him.”
Marlene and Peter kept making jokes about it while James looked like he was going to run away and change his name before saying anything to Sirius.
And the three spent the rest of the afternoon like that, making jokes with each other and having a good time that reminded them of the good times they had when they were young children and it was just the three of them against the world.
In the evening they went back to the common room rejoining their friends. When James entered the room he made immediate eye contact with Sirius who smiled brightly at him. James smiled back but he quickly looked when he was reminded of his conversation earlier, he couldn’t help but feel guilty about not telling him that he was dating Regulus but he was too scared.
On the other side of the room Sirius frowned at James' reaction and turned to look at Remus, but the latter just shrugged, he didn’t know what was going on with James either.
The rest of the evening was spent quietly with no more incident, even if Sirius couldn’t help but feel like something was wrong with his best friend. He could tell that there was something with Peter as well, as he kept glancing in his direction and then at James.

For the rest of the week, Sirius felt like James really was acting strangely and he was pretty sure that he wasn’t the only one noticing it. He was also almost sure that Peter and Marlene knew what was going on, they were not the most discreet of his friends.
The week-end started peacefully, as peaceful as a week-end can be for the Gryffindors. But during the day, Peter was acting weirder than usual and nobody could understand why. Well except James and Marlene who figured that their friends were uncomfortable with keeping a secret from his friends. And as soon as Peter found himself alone with Remus all of his resilience cracked and he confessed James’ secret to him.
“Oh my god. Oh my god, oh my god, can you forget what I just said ? I wasn’t supposed to tell anyone ! Oh my god James is going to kill me. Please don’t tell him I’m the one who told you !”
Remus chuckled lightly before answering “Peter, I already knew about James and Regulus. They’re not exactly discreet.”
“What ? I didn’t know before he told me.” Peter mumbled his answer.
“I’m just a good observer.”
They stayed in silence for a few seconds before Peter broke it “Wait ! If you figured it out, do you think Sirius did as well ?”
“I doubt it, he would’ve probably said something or murdered James”
“Umm, so you also think that Sirius is not going to be happy with this news… James has been panicking about it all week, that’s why he’s acting weird.”
“Yeah… Hopefully, it won’t be as bad as we think but I don’t have a lot of hope…”

At the same time, James and Sirius were studying together in a study room in silence. An odd sight as those two could never stop talking when they were with each other, but James could not mutter a word, he was terrified that if he started speaking he would spill everything and Sirius would never want to talk to him ever again. On the other hand, Sirius was getting frustrated, he was trying to find out if he said or did anything wrong to make James act like this around him.
It was only a matter of minutes before one of them burst out everything that was on their mind. Whether they will end the day laughing at their stupidity or mad at each other will just depend on who will start talking first.

A few hours later, Peter, Remus, Lily, Mary, and Marlene were working together in the common room when Sirius entered the room and directly went to his dorm room without sparing a glance at them and looking pretty angry. They looked at the door he had just violently closed behind him in silence not fully understanding what just happened.
Lily was the first one to break the silence wondering what was wrong with their friend. But before anyone could answer, James entered the common room looking like a kicked puppy.
“Uh-uh, is Sirius mad because you told him ?” Marlene asked, clearly trying not to laugh at the sigh on James’ face.
“No… I didn’t even tell him, we got into an argument and he got mad and left…”
“What kind of argument did you guys get into for him to be that mad ? He really looked like he was about to kill the next person that would pass his way.”Mary asked.
“He asked me why I was acting so weird and I told him I didn’t know what he was talking about and he told me to stop lying and then we might have started to argue more and more and then he left because he was very mad…” James explained and then added quietly “He told me not to talk to him until I figured my shit out…”
“I don’t want to like, come in the middle of your argument but you have been acting weird lately, especially around Sirius. I’m pretty sure everybody noticed.” Mary gently said to James.
“I know ! But I’m so stressed about everything and I’m trying to tell him something but I’m scared of his reaction and I don’t want him to be mad but I clearly messed up because he’s mad anyway but I feel like he would be madder if I had told him what I’m trying to tell him !”
“Is it…” Lily started to ask carefully, “Is it about you and Regulus ?”
“Yes ! Of course it is ! What else could I be talking about ?” Then, James turned around slowly towards her and squinted his eyes “Wait. How do you know about me and Reggie ?”
“James you’re not very discreet, neither is Regulus which is quite surprising for someone who is so quiet all the time.”
“Oh my god, oh my fucking god, do all of you know ?”
“I mean Peter did accidentally tell me but I already knew yeah.”
“Me and Mary knew… We can hear you trying to sneak out of the dorms at midnight almost every day.”
“What ? Oh my god, I’m so stupid.”
“If I can reassure you, James, I’m pretty sure neither Marlene nor I had any ideas until you told us. Maybe because we’re kind of oblivious but still !”
“Yeah… Thanks Peter.”
“Also… I’m not completely sure but there is a chance that Sirius already knows about it.” Lily said hesitantly, not trying to freak James out even more than he already was.
James started opening his mouth to continue panicking about all of his friends knowing his supposedly secret relationship but a voice cut him off.
“Are you fucking kidding me ? Of course I already know about you shagging my brother every night in the astronomy tower. Don’t tell me that’s why you’ve been weird all this time ?” Sirius sounded exasperated at James, and the concern couldn’t help but wince.
“So, you knew ?”
“Yes, I knew James, I’ve known since the beginning of your relationship.”
“And you’re not mad ?”
“Why would I be mad ? You guys are clearly happy together and Regulus is starting to be less of little shit with me so, only good points. Also, if you guys get married we will be officially brothers mate !” Sirius said excitedly.
“Oh my god, you’re right ! I’m so sorry I didn’t tell you sooner, I was scared.”
As James said that, the two best friends hugged each other to steal their reconciliation.
“So, you guys argued for nothing ? Bouh I wanted the gossip.”
“Shut up Marlene.”
The rest of the evening was spent with laughter and joy, even after Regulus and his friends joined them.